In the Linux kernel, the following vulnerability has been resolved:

net/nfc: fix use-after-free llcp_sock_bind/connect

Commits 8a4cd82d ("nfc: fix refcount leak in llcp_sock_connect()")
and c33b1cc62 ("nfc: fix refcount leak in llcp_sock_bind()")
fixed a refcount leak bug in bind/connect but introduced a
use-after-free if the same local is assigned to 2 different sockets.

This can be triggered by the following simple program:
int sock1 = socket( AF_NFC, SOCK_STREAM, NFC_SOCKPROTO_LLCP );
int sock2 = socket( AF_NFC, SOCK_STREAM, NFC_SOCKPROTO_LLCP );
memset( &addr, 0, sizeof(struct sockaddr_nfc_llcp) );
addr.sa_family = AF_NFC;
addr.nfc_protocol = NFC_PROTO_NFC_DEP;
bind( sock1, (struct sockaddr*) &addr, sizeof(struct sockaddr_nfc_llcp) )
bind( sock2, (struct sockaddr*) &addr, sizeof(struct sockaddr_nfc_llcp) )
close(sock1);
close(sock2);

Fix this by assigning NULL to llcp_sock->local after calling
nfc_llcp_local_put.

This addresses CVE-2021-23134.

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00015.

Exploitation none

Automatable no

Technical Impact total

Affected Vendors & Products

Vendors Products
Linux
  • Linux Kernel

Configuration 1 [-]

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://git.kernel.org/stable/c/18175fe17ae043a0b81e5d511f8817825784c299 cve-icon cve-icon
https://git.kernel.org/stable/c/18ae4a192a4496e48a5490b52812645d2413307c cve-icon cve-icon
https://git.kernel.org/stable/c/26157c82ba756767b2bd66d28a71b1bc454447f6 cve-icon cve-icon
https://git.kernel.org/stable/c/374cdde4dcc9c909a60713abdbbf96d5e3e09f91 cve-icon cve-icon
https://git.kernel.org/stable/c/48fba458fe54cc2a980a05c13e6c19b8b2cfb610 cve-icon cve-icon
https://git.kernel.org/stable/c/6b7021ed36dabf29e56842e3408781cd3b82ef6e cve-icon cve-icon
https://git.kernel.org/stable/c/c61760e6940dd4039a7f5e84a6afc9cdbf4d82b6 cve-icon cve-icon
https://git.kernel.org/stable/c/ccddad6dd28530e716448e594c9ca7c76ccd0570 cve-icon cve-icon
https://git.kernel.org/stable/c/e32352070bcac22be6ed8ab635debc280bb65b8c cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2024022955-CVE-2021-47068-a416@gregkh/T/#u cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2021-47068 cve-icon
https://www.cve.org/CVERecord?id=CVE-2021-47068 cve-icon
History

Tue, 22 Apr 2025 16:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

 ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Tue, 10 Dec 2024 20:15:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
Metrics cvssV3_1

{'score': 7.3, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H'}

 cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

Mon, 04 Nov 2024 13:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T07:03:32.020Z

Reserved: 2024-02-29T22:33:44.296Z

Link: CVE-2021-47068

cve-icon Vulnrichment

Updated: 2024-08-04T05:24:39.447Z

cve-icon NVD

Status : Modified

Published: 2024-02-29T23:15:08.170

Modified: 2025-04-22T16:15:20.727

Link: CVE-2021-47068

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-02-29T00:00:00Z

Links: CVE-2021-47068 - Bugzilla

cve-icon OpenCVE Enrichment

No data.